1. Technical
The present disclosure relates generally to apparatuses for cooling a superconducting quantum interference device and, more particularly, to apparatuses for indirectly cooling a superconducting quantum interference device.
2. Description of the Related Art
A superconducting quantum interference device (hereinafter referred to as “SQUID”) is an ultrasensitive sensor which is capable of measuring a hyperfine magnetic field generated in biological activities of heart, brain, muscles, and the like. A SQUID sensor operates at extremely low temperature of 4K or 77K. Measurement sensitivity is several to tens of fT/√Hz. In general, liquid nitrogen or liquid helium is used to cool the SQUID sensor to low temperature. A low-temperature coolant storage container is required to store such a low-temperature coolant.